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@@ -155,7 +155,9 @@ <h2>Definitions of Standard ML</h2>
 Both of these design critiques are somewhat outdated because they
 predate the revised Definition.
 
-<h2>Mailing lists</h2>
+<h2>Community</h2>
+
+<h3>Mailing lists</h3>
 The SourceForge project hosts two mailing lists relating to Standard
 ML. Visit the info page for a list to subscribe.
 <blockquote>
@@ -172,6 +174,32 @@ <h2>Mailing lists</h2>
 http://lists.sourceforge.net/lists/roster/sml-list</a>
 </blockquote>
 
+MLton has a users and a developers list:
+<blockquote>
+Name: MLton-user<br>
+Address: <a href="mailto:MLton-user@mlton.org">MLton-user@mlton.org</a><br>
+Subscribe: <a href="https://lists.sourceforge.net/lists/listinfo/mlton-user">lists.sourceforge.net/lists/listinfo/mlton-user</a><br>
+Archive: <a href="https://sourceforge.net/mailarchive/forum.php?forum_name=mlton-user">sourceforge.net/mailarchive/forum.php?forum_name=mlton-user</a><br>
+<br>
+Name: MLton-devel<br>
+Address: <a href="mailto:MLton-devel@mlton.org">MLton-devel@mlton.org</a><br>
+Subscribe: <a href="https://lists.sourceforge.net/lists/listinfo/mlton-devel">lists.sourceforge.net/lists/listinfo/mlton-devel</a><br>
+Archive: <a href="https://sourceforge.net/mailarchive/forum.php?forum_name=mlton-devel">sourceforge.net/mailarchive/forum.php?forum_name=mlton-devel</a><br>
+</blockquote>
+
+<h3>Chat</h3>
+There is a public chat room for Standard ML at <a href="matrix://#standardml:matrix.org">#standardml:matrix.org</a> using the Matrix protocol.
+You can join the chat using any matrix client.
+<br>
+For a one-click web-based interface use this link: <a href="https://app.element.io/#/room/#standardml:matrix.org">app.element.io/#/room/#standardml:matrix.org</a>
+
+<p>
+Matrix is a free open source federated protocol for chat. It has several open implementations, and a lot of good open source clients for Windows, Mac, Linux, web-based, Android and iOS. See <a href="https://matrix.org/">matrix.org/</a> for a full sales pitch.
+</p>
+
+<h3>Reddit</h3>
+There is an active reddit community discussing everything related to Standard ML at <a href="https://www.reddit.com/r/sml/">reddit.com/r/sml/</a>
+
 <h2>Successor ML</h2>
 <p>
 Recently discussions of improvements and extensions of the Standard ML design